HIV is a contagious disease caused by HIV infection, which is usually transmitted through sexual contact, and in some cases through blood transmission or vertical transmission from mother to child. If HIV-infected mothers and newborns are given effective prevention and treatment, the rate of infection will be greatly reduced. It is important to note that HIV-infected mothers should avoid breastfeeding as much as possible to prevent the transmission of HIV from breast milk to their children. HIV has not been found to be transmitted through the respiratory tract, food, sweat, tears, insect bites, handshakes, etc.